title: 9,10-Dihydroergotalkaloids as inhibitors of acetylcholinesterase.
abstract: A kinetic analysis of the interaction of 9,10-dihydroergotalkaloids with electrophorus electricus acetylcholinesterase [E.3.1.1.7] and acetylthiocholine as substrate shows a mixed type of inhibition of this enzyme. The inhibitor constants Ki were found to be for 9,10-dihydroergokryptine 198 mumol, 9,10-dihydroergotamine 144 mumol, 9,10-dihydroergocristine 117 mumol. A more potent inhibitor is ergotamine with the inhibitor constant Ki = 15 mumol and a mixed type of inhibition.
mesh_terms: D000818:Animals; D002800:Cholinesterase Inhibitors; D004087:Dihydroergotamine / Q000494:pharmacology; D004088:Dihydroergotoxine / Q000494:pharmacology; D004557:Electric Organ / Q000201:enzymology; D004593:Electrophorus; D004876:Ergot Alkaloids / Q000494:pharmacology*; D066298:In Vitro Techniques; D007700:Kinetics
chemical_list: D002800:Cholinesterase Inhibitors; D004876:Ergot Alkaloids; D004088:Dihydroergotoxine; D004087:Dihydroergotamine